EP1565625B1 - Flexible thermal insulation material comprising at least one open-work layer - Google Patents

Abstract

The insulation material, having a total thickness of under 10 cm, consists of at least one supple layer (2, 4, 6, 8, 10) of wadding or felted natural or synthetic fibres, and layers of supple and reflective film. The fibre layers, separated by intermediate film layers (3, 5, 7, 9), have holes (17) containing gas that is normally in contact with the film layers. The holes are in zones (24) of increased thermal resistance and accounting for more than half the area of such zones. One side of the insulation material has a layer of a covering film (1) of non-woven fibres that is impermeable to water but permeable to vapour.

Description

The invention relates to a flexible thermal insulation material comprising at least one insulating flexible sheet covered, on at least one side, by a flexible reflective film. The invention relates in particular to a thin thermal insulation material (less than 10 cm), said multilayer thin insulation, in strips or other flexible panels (square flexible parts for example) for the thermal insulation of buildings, comprising a alternation of reflective soft films and insulating soft layers of insulating material.

The insulation according to the invention is particularly intended for the insulation of roofs and attic (laying under rafters, on rafters, on battens, etc.), ceilings and attics lost (laying under trusses, under or on floor, etc. .), floors (laying on or underfloor), vertical walls and walls, and, where applicable, hydraulic heating floors, electric radiant floors, garage doors, rolling shutter boxes, etc.

Thermal exchanges result from three simultaneous modes of transmission: conduction, convection and radiation. To jointly minimize these three phenomena is difficult: interposing a solid wall between two different temperature environments avoids any convective exchange between the two media but induces significant exchanges by conduction and transmission and emission of thermal radiation; making a gas strip between two solid walls of different temperatures limits the conduction phenomena but generates radiation exchanges between the two walls. The design of a thermal insulation material therefore results from a compromise, which must also take into account economic constraints (which require the design of inexpensive materials) and industrial constraints that require the design of materials that are both flexible - in order to facilitate their packaging, transport and installation-, light-in order to limit the corresponding loads supported by the structure of the building-, and thin-in view of limit the loss of volume or living space due to the thickness of the insulation material or, for a given volume or living area, the size and cost of the building structure.

• les matériaux d'isolation dits isolants épais, d'épaisseur supérieure à 15 cm et très souvent supérieure à 20 cm, qui comprennent généralement une unique nappe épaisse d'un matériau fibreux minéral tel que la laine de roche ou la laine de verre, ou d'un matériau fibreux végétal tel que la laine de chanvre ou la laine de lin, ou encore d'un matériau fibreux animal tel que la laine de mouton. Ladite nappe est couverte de chaque côté par un film de protection en papier Kraft® ou en polypropylène. Ces isolants présentent une résistance thermique satisfaisante, du fait de leur épaisseur (la résistance thermique de la nappe étant sensiblement proportionnelle à son épaisseur), du caractère fibreux de la nappe, et du choix d'une matière de faible conductivité thermique pour la réalisation desdites fibres. Les échanges par transmission radiative sont par ailleurs minimisés par le choix de films de protection opaques. En revanche, ces films de protection présentent une émissivité non négligeable qui favorise les transferts d'énergie par rayonnement, prépondérants lorsque l'écart de température entre l'extérieur et l'intérieur est important. Ces isolants sont de plus, par définition, particulièrement encombrants et lourds, et par conséquent mal adaptés aux applications de réhabilitation ou de rénovation de bâtiments existants, pour lesquels la perte de volume ou de surface imputable à l'isolant et la surcharge que celui-ci impose à la structure du bâtiment n'ont pas été initialement prises en compte. Dans certains cas, l'emploi de ces isolants est même incompatible avec la structure existante ;
• les matériaux d'isolation thermique dits isolants minces, d'épaisseur inférieure à 10 cm et très souvent inférieure à 5 cm, qui comprennent une pluralité de films souples métallisés et de couches souples intercalaires en matériau isolant. La réflectivité des films est utilisée pour limiter les transferts thermiques par rayonnement. En effet, lorsqu'un rayonnement incident émanant d'un milieu chaud atteint une face réfléchissante d'un film, la grande majorité de son énergie est réfléchie vers le milieu chaud sans pénétrer dans le film, de sorte que la fraction de son énergie absorbée, et donc ré-émise par le film, est faible (la fraction d'énergie directement transmise au milieu plus froid situé de l'autre côté du film étant par ailleurs nulle ou négligeable dans le cas d'un film opaque). Et la superposition de plusieurs films métallisés distants permet de réduire progressivement, et de façon plus efficace, les échanges par rayonnement entre deux milieux. Les échanges par rayonnement et par convection entre deux films successifs sont par ailleurs limités par interposition d'une couche intercalaire isolante entre lesdits films. La couche intercalaire joue le rôle d'un espaceur optique permettant de séparer les deux films réfléchissants, afin d'éviter tout pont thermique par contact (conduction) entre les deux films. Il existe plusieurs types connus de couche intercalaire pour isolant mince multicouche, parmi lesquels :
  • les couches en matériau fibreux, et notamment les nappes en matériau fibreux synthétique telles que les ouates en polyester (ou éventuellement les nappes en un matériau fibreux minéral, végétal ou animal -laine de verre, laine de roche, laine de chanvre, laine de mouton-, éventuellement imprégné de résines synthétiques),
  • les couches en mousse alvéolaire à cellules fermées ou ouvertes, en une matière synthétique telle qu'un polyéthylène ;
  • les films à bulles, qui présentent, selon une direction orthogonale à la couche, une ou plusieurs rangées de poches fermées (dites bulles) en matière synthétique, mesurant 5 à 20 mm de diamètre et contenant de l'air,
  • les grilles tissées ou extrudées, telles que les grilles de mousse synthétique évoquées par FR-2 765 305 dans sa partie introductive, ou encore les filets décrits par US-4 230 057 , tricotés, tissés, formés de cordes, fils, filaments ou fibres, ou fabriqués par extrusion ou par perforation ou par perforation et expansion de toiles plastiques ou non-tissées.

There are two main families of thermal insulation materials today:

• insulation materials said to be thick insulators, with a thickness greater than 15 cm and very often greater than 20 cm, which generally comprise a single thick ply of a mineral fibrous material such as rockwool or glass wool, or a fibrous plant material such as hemp wool or linen wool, or an animal fibrous material such as sheep wool. Said sheet is covered on each side with a protective film of Kraft® paper or polypropylene. These insulators have a satisfactory thermal resistance, because of their thickness (the thermal resistance of the sheet being substantially proportional to its thickness), the fibrous nature of the sheet, and the choice of a material of low thermal conductivity for the realization of said fibers. Radiative transmission exchanges are also minimized by the choice of opaque protective films. On the other hand, these protective films have a non-negligible emissivity which favors radiant energy transfers, predominant when the difference in temperature between the outside and the inside is important. These insulators are also, by definition, particularly cumbersome and heavy, and therefore poorly adapted to the applications of rehabilitation or renovation of existing buildings, for which the loss of volume or area attributable to the insulation and the overload that it This imposes on the structure of the building were not initially taken into account. In some cases, the use of these insulators is even incompatible with the existing structure;
• the so-called thin insulating thermal insulation materials, of thickness less than 10 cm and very often less than 5 cm, which comprise a plurality of metallized soft films and interlayer flexible layers of insulating material. The reflectivity of the films is used to limit heat transfer by radiation. Indeed, when an incident radiation emanating from a hot medium reaches a reflective surface of a film, the great majority of its energy is reflected towards the hot medium without penetrating the film, so that the fraction of its energy absorbed, and thus re-emitted by the film, is low (The fraction of energy directly transmitted to the colder medium located on the other side of the film is otherwise zero or negligible in the case of an opaque film). And the superposition of several distant metallized films makes it possible to reduce, progressively and more effectively, the radiation exchanges between two media. The exchanges by radiation and convection between two successive films are further limited by the interposition of an insulating interlayer between said films. The interlayer plays the role of an optical spacer to separate the two reflective films, to avoid contact thermal bridge (conduction) between the two films. There are several known types of interlayers for multilayer thin insulation, among which:
  • the layers of fibrous material, and in particular the plies of synthetic fibrous material such as polyester wadding (or possibly the plies made of a mineral fiber material, vegetable or animal-glass wool, rock wool, hemp wool, sheep wool - possibly impregnated with synthetic resins),
  • closed-cell or open cell foam layers made of a synthetic material such as polyethylene;
  • bubble films, which have, in a direction orthogonal to the layer, one or more rows of closed pockets (called bubbles) of synthetic material, measuring 5 to 20 mm in diameter and containing air,
  • woven or extruded grids, such as synthetic foam grids evoked by FR-2 765 305 in its introductory part, or the nets described by US 4 230 057 , knitted, woven, of ropes, threads, filaments or fibers, or manufactured by extrusion or by perforation or perforation and expansion of plastic or non-woven fabrics.

Thin insulators are particularly suitable for retrofit and retrofit applications of existing buildings, as well as for specific applications (such as insulating a floor or screed receiving a floating floor). However, regardless of the type of interlayer used, their thermal efficiency is still considered insufficient, considering that it is often less than that of the thickest insulation the best.

US 4 230 057 advocates the use of a net as an interlayer, which provides interesting results. The size of the meshes of the net is chosen low enough so that the films do not touch, and the largest possible to benefit from the effects of film-to-film reflexivity. But progress remains to be made in the efficiency of the intermediate layers in terms of thermal insulation.

In addition, the inventor has found that the grids and anterior threads also have mechanical disadvantages, and in particular a too low tensile strength and high deformability in the diagonal directions of the mesh of the grid (or net). These disadvantages are troublesome for both the manufacture of grids or nets and the material, for the conditioning of the material and the laying thereof; they force to handle the grids (or nets) and the material with great care to avoid any tearing and deformation of said grids.

The invention aims to overcome these drawbacks by proposing a flexible thermal insulation material having improved thermal insulation properties, as well as an interlayer having a reinforced mechanical strength.

In particular, an object of the invention is to provide a thin insulating material, with a total thickness of less than 10 cm, and in particular less than 5 cm, with increased thermal insulation performance and in particular greater than those of thick anterior insulators.

The invention also aims to provide an intermediate layer with improved insulation properties, having in addition greater tear resistance and lower deformability at least in certain directions.

Another objective of the invention is to propose a thermal insulation material, and a corresponding laying method, making it possible to obtain, without significant extra thickness, improved thermal insulation at the junctions between the strips. or other adjacent panels of material. In particular, the invention aims to provide a waterproof material (rainwater, runoff, slush, powder snow) and a method of laying such a material that is simple and fast, and that allows to guarantee a perfect watertightness of the joints between the strips or other panels of material.

Another object of the invention is to provide a material providing the aforementioned advantages and whose cost of return "supplied posed" (this cost including all the costs related to the manufacture and installation of the material) remains similar to the cost "Provided laid" mean of previous known thermal insulation materials.

In all the following, a face of a body (of a film for example) of the material according to the invention is said to be of little emissivity since it has a directional monochromatic emissivity ε _{λ, δ} less than 0.2 for wavelengths λ of between 400 and 800 nm, and preferably for wavelengths between 300 and 1000 nm, or even for all wavelengths (gray body), for directions δ substantially orthogonal to said face - and preferably for all directions (isotropic emissivity) -, and for body temperatures corresponding to normal conditions of use of the material.

In addition, a face of a body (of a film for example) of the material according to the invention is said to be reflective since it has a reflectivity ρ _{λ, i} monochromatic directional (hemispherical or specular) greater than 0.8 for wavelengths λ of between 400 and 800 nm, and preferably for wavelengths of between 300 and 1000 nm, or even for all wavelengths, for directions of incident radiation substantially orthogonal to said face -and preferably for all directions of incidence-, and for conditions (body temperature, luminance of the incident flux ...) normal use of the material.

Furthermore, "web" means an intermediate layer which is in the form of a flexible web or other flexible panel (of a any one), made of a flexible insulating material having a cohesion own. Such a sheet is, in addition, thicker than each film covering it. This definition of a sheet does not include the solid intermediate layers, the non-continuous intermediate layers formed of point and independent separation shims (such as the "calming pieces" described by FR-2 765 305 ), and the padding of bulk material devoid of proper cohesion when the bulk material is not adhered to a film or held between two films. The invention applies essentially to a material comprising at least one such sheet.

• couverte d'un côté au moins par un film souple, dit film réfléchissant, présentant une face à la fois réfléchissante et peu émissive, et/ou deux faces peu émissives, et/ou deux faces réfléchissantes,
• et pourvue d'au moins une lumière traversante, dite lumière d'isolation, contenant un volume de gaz venant normalement au contact de chaque portion de film en regard de la lumière d'isolation, chaque lumière d'isolation ayant une section frontale dépourvue d'angle vif.

The invention relates to a flexible thermal insulation material comprising at least one flexible sheet and at least one flexible film superimposed, comprising at least one flexible sheet, called perforated sheet,

• covered on one side at least by a flexible film, said reflective film, having a both reflective and low-emissivity side, and / or two low emissivity faces, and / or two reflecting faces,
• and provided with at least one through-light, called the insulating light, containing a volume of gas normally coming into contact with each film portion facing the insulating light, each insulating light having a front section devoid of 'sharp corner.

Advantageously and according to the invention, the perforated sheet comprises at least one zone, called the resistive zone, of greater thermal resistance, in which are provided insulation lights defining a total opening area greater than half the area. of the resistive zone, all of said resistive zones extending over more than half of the area of the perforated sheet.

The expression "the volume of gas (contained in each of the insulating lights) normally coming into contact with each portion of film opposite the insulating light" means that the volume of gas is at least in contact with, one side of the perforated sheet, reflective film on the entire portion of said film delimited by the insulating light. On the other side of the openwork tablecloth, he is contact of a portion -limited by the insulating light-of another film if the sheet is covered on both sides by a film, or of a wall to be isolated if the sheet forms a front face of the material and is (in use) applied against such a wall or extended opposite and at a distance from such a wall. In other words, under normal conditions of use and implementation of the material according to the invention, the volume of gas contained in the insulating light is interposed between the two films that separates the perforated sheet (or well between the film covering the web and a wall opposite which it is applied), so that the two films (or the film and the wall) do not come into contact with each other. Any thermal bridge between the two films (or between the film and the facing wall) through the insulation light is thus avoided.

Note that, under normal conditions of use and implementation, the material is unfolded, extended substantially flat against a wall, or fixed on a support (such as a lattice of cleats) substantially parallel to a wall or other generally flat surface (surface defined by the roof covering, for example). Conversely, when the material is folded or wound on itself, for transport for example, it is not excluded that, because of their flexibility and the compressibility of the web, two films facing each other. touch each other through an insulation light.

The invention therefore consists in using, as interlayer, a sheet in which have been formed one or more isolation lights without sharp angle.

The presence of these insulating lights between two successive films has two opposite effects: it leads to a reduction in energy exchanges by conduction between the two films, but promotes the energy exchanges by radiation and convection between them. The use of a reflective film on at least one side of the web makes it possible to partially compensate for the increase in radiation exchanges, and it proves a posteriori that these contrary effects ultimately result in an improvement in the performance of thermal insulation of the material (under conditions-especially temperature-normal use and implementation of the material). It should be noted that the radiation transfers through a reflective film as defined above, are limited regardless of the side of the film where the hot medium is located, so that the material is effective in summer and winter.

• de façon inexpliquée, ladite forme semble à l'origine d'une amélioration des performances d'isolation de la nappe dans une mesure inattendue. L'inventeur a en effet constaté que la comparaison des performances d'isolation entre une nappe ajourée selon l'invention et une nappe de même nature et de même épaisseur, mais dépourvue de lumières d'isolation, aboutit à un rapport bien supérieur au rapport résultant de la comparaison entre une grille de mousse antérieure et une couche de mousse de même nature et de même épaisseur que la grille (mais dépourvue de mailles). Les performances d'isolation d'une telle nappe ajourée dépassent donc toutes les prévisions possibles,
• la forme des lumières d'isolation confère une plus grande résistance mécanique à la nappe, et notamment une plus grande résistance à la traction dans toutes les directions contenues dans un plan frontal de la nappe. L'inventeur a en effet constaté que les éventuelles déchirures qui apparaissent dans les grilles antérieures connues naissent principalement dans les angles des mailles de la grille, où les contraintes de fendage sont les plus importantes. La forme arrondie (dépourvue d'angle vif) des lumières d'isolation selon l'invention permet de répartir les contraintes subies par la lumière d'isolation sur l'ensemble de son périmètre, d'éviter une concentration de contraintes de fendage en un point de ce périmètre et donc de limiter la formation de déchirures,
• elle diminue également la déformabilité de la nappe ajourée, en répartissant, sur l'ensemble de leur périmètre et dans toutes les directions, les efforts éventuellement subis par les lumières. En définitive, l'amélioration de la tenue mécanique de la nappe (plus grande résistance au déchirement et plus faible déformabilité) facilite la fabrication et les manipulations ultérieures du matériau,
• pour les deux précédentes raisons, la forme arrondie des lumières d'isolation selon l'invention permet de réaliser des lumières dans une nappe fibreuse, notamment par découpage, sans risquer de voir la nappe se déchirer lors du retrait des chutes découpées pour former lesdites lumières. Il est alors possible d'envisager une fabrication industrielle et rentable de telles nappes ajourées fibreuses.

The form of the insulation lights according to the invention has several advantages:

• inexplicably, said shape seems to be causing an improvement in the insulation performance of the web to an unexpected extent. The inventor has indeed found that the comparison of the insulation performance between a perforated sheet according to the invention and a sheet of the same type and thickness, but devoid of insulation lights, results in a much higher ratio to the ratio resulting from the comparison between an earlier foam grid and a layer of foam of the same nature and the same thickness as the grid (but devoid of mesh). The insulation performance of such a perforated sheet thus exceeds all possible forecasts,
• the shape of the insulation lights gives greater mechanical strength to the sheet, and in particular greater tensile strength in all directions contained in a frontal plane of the sheet. The inventor has indeed found that any tears that appear in known prior grids arise mainly in the grid grid angles, where the splitting constraints are the most important. The rounded shape (devoid of acute angle) of the insulation lights according to the invention makes it possible to distribute the stresses to which the insulating light is subjected over its entire perimeter, to avoid a concentration of splitting stresses in one point of this perimeter and therefore to limit the formation of tears,
• it also reduces the deformability of the perforated sheet, by spreading, over their entire perimeter and in all directions, the forces possibly experienced by the lights. Ultimately, improving the mechanical strength of the web (greater tear resistance and lower deformability) facilitates the manufacture and subsequent handling of the material,
• for the two previous reasons, the rounded shape of the insulation lights according to the invention makes it possible to produce lumens in a fibrous sheet, in particular by cutting, without the risk of seeing the sheet tearing during the removal of the cut-out falls to form said lights . It is then possible to envisage an industrial and profitable manufacture of such fibrous perforated sheets.

Advantageously and according to the invention, the openwork web is made of a nonwoven fibrous material, thermally bonded and / or needled and / or bonded. Such a perforated sheet thus differs from prior grids or nets known (e) s, not only by the shape of its insulation lights, but also by its nature and its structure. Such a sheet has two levels of ajourage: on the one hand, the space between the intermingled fibers, which forms a multitude of tortuous galleries of the order of one micron (possibly up to the millimeter), and other the insulating lights through which the reflective films (or the film and the wall) are directly opposite. The thermal results of such a fibrous openwork web are particularly satisfactory.

In a variant, the perforated sheet is made of synthetic foam.

The perforated sheet preferably has a multitude of insulation lights. Each of these isolation lights is arranged so as to avoid the formation of a thermal bridge through the insulating light. In particular, the dimensions of each insulating light, the thickness of the perforated sheet and the flexibility of each film that covers it, are adapted to prevent inadvertent contact (under normal conditions of use and implementation of the material ), through said insulating light, between the reflective film and a film or a wall facing the other side of the perforated web. Note that the perforated web is preferably covered on each side by a flexible reflective film.

The insulation lights are made by stamping the sheet, or by cutting the sheet by means of mechanical cutting tools (for example, rotary cylinder with cutting blades, and associated counter-cylinder), thermal, optical (laser), hydraulic (high pressure water jet), vibratory high frequency (ultrasound) ...

Advantageously and according to the invention, each insulating light has a maximum dimension of less than ten times the thickness of the perforated sheet. By "dimension of a light" is meant a dimension of light in a frontal plane of the web. The maximum dimension of light is its largest dimension in such a frontal plane.

In particular, the perforated sheet advantageously has a thickness (at rest) of between 1 and 12 mm, preferably of the order of 8 mm, and each insulating light has a maximum dimension of between 10 and 30 mm. preferably of the order of 20 mm.

Advantageously and according to the invention, the perforated sheet has insulation lights of circular section. This form of insulation lights gives: the best results in terms of mechanical strength and deformability of the perforated sheet, and in terms of thermal insulation.

As a variant or in combination, the perforated sheet has oval or elliptical section insulation lights. This form also provides satisfactory results. Note that the same perforated sheet can include different forms of insulation lights.

Advantageously and according to the invention, the insulation lights of a resistive zone of the perforated sheet are aligned in two orthogonal directions, and in particular in a longitudinal direction and in a transverse direction of the material. If the material is in the form of a web, the longitudinal and transverse directions of the material correspond respectively to the directions of the length of the web and its width (width). If it is a square panel, the longitudinal and transverse directions of the material respectively correspond to the directions of two adjacent sides of the panel.

Alternatively, the insulation lights of a resistive area are arranged in staggered rows. They are for example aligned in a longitudinal direction of the material and offset in a transverse direction thereof, or, conversely, aligned in the transverse direction and offset in the longitudinal direction.

These two distributions, not only confer good mechanical strength to the openwork web, but also optimizing, in an unexplained way, its results in terms of thermal insulation. It should be noted that the same sheet may have resistive zones having different distributions.

Advantageously and according to the invention, the resistive zone (s) form (s) a (of) band (s) in the perforated sheet, and in particular a longitudinal band (s), extending mainly longitudinally, preferably over the entire length of the material, or one or more transverse webs extending transversely, possibly over the entire width of the material, or separate rectangular areas both by solid longitudinal strips and by solid transverse strips (a solid band being devoid of insulating light).

In a preferred version of the invention, the material comprises a plurality of plies and each of the plies of the material is perforated according to the invention. A material comprising at least one perforated sheet, as well as one or more other non-perforated interlayer layers such as known prior layers, is also in accordance with the invention. If the material comprises a plurality of perforated layers according to the invention, they may all be identical or, conversely, have different characteristics (nature and thickness of the sheet, shape, size and distribution of insulation lights ...).

The material according to the invention preferably has a total thickness of less than 10 cm, and in particular less than 5 cm (it advantageously has 4 to 6 plies, preferably perforated).

Advantageously and according to the invention, each perforated sheet is a wadding or felt or fleece of a nonwoven fibrous material (thermally bonded and / or needled and / or glued) made from a material chosen from synthetic materials made of polyester , polyamide, chlorofibres, polyolefin (polyethylene, polypropylene ...), artificial materials such as viscose rayon, natural plant materials such as cotton, hemp, flax, natural animal materials such as sheep's wool, mixtures of many of the aforementioned materials. The fibers used may be solid or hollow (preferably hollow). They are advantageously elastic.

The thermal insulation material according to the invention preferably comprises at least two layers (and in particular two perforated layers) separated by a flexible reflecting film, said intermediate film. Advantageously and according to the invention, each intermediate film is made of a synthetic material chosen from polyolefins such as polyethylenes and polypropylenes, polyesters such as polycarbonates, polyethers, polyurethanes, polystyrenes, polyvinyl chlorides, and mixtures of several of the previously mentioned subjects. Each intermediate film advantageously has at least one face covered with a reflective metal coating such as aluminum, by vacuum deposition or by doubling or by coating. Such a face is little emissive and reflective, given the material constituting the film and its metal coating.

The thermal insulation material according to the invention preferably comprises an outer film, called a cover film, having an outer face forming a front face of the material, preferably intended to be oriented towards the outside of the building or the room to be insulated. . Advantageously and according to the invention, said cover film is watertight and permeable to water vapor, and has a breaking strength greater than 150 N. It is preferably a nonwoven, produced in a material chosen from polypropylenes, polyesters, viscose rayon, mixtures of several of the abovementioned materials. Its outer face is advantageously embossed and / or calendered and / or primed in order to improve the mechanical strength and enhance the strength of the film. It is also preferably covered with a reflective metal coating such as aluminum, by vacuum deposition or doubling or coating, so as to have a high reflectivity (preferably whatever the incident radiation, its wavelength, its angle of incidence, the material constituting the film, etc.).

Such a cover film constitutes a waterproof and resistant film, capable of protecting the material and the interior of a building against dust, rain, powdery snow, etc. It thus fulfills the functions of the films known under the name rainscreen wallpaper. Roofing screens are known formed of a ribbon frame, coated on both sides with an asphalt dusted with non-adherent talc, and optionally metallized on one side. Underlays are also known formed of a reflective metallized polyolefin film, provided with a mechanical reinforcing grid and coated with flame retardant polymers. Known roofing screens are intended for the protection of ventilated roofs, or closed attics if they are microperforated (to be permeable to water vapor).

In a preferred version of the invention, the material therefore incorporates a new under-roof rainscreen screen and a new multilayer insulation, the combination of which offers new advantages. It gives a greater mechanical strength to both the under-roof screen and the insulation, facilitates the installation of the insulation (whose mechanical strength is improved by the presence of the screen), reduced considerably the installation time and the corresponding costs since only one product offering both waterproofing and insulation is installed, instead of two previously ...

The thermal insulation material according to the invention more preferably comprises an outer film, called finishing film, having an outer face forming a front face of the material (end face opposite to that formed by the cover film) preferably intended for be oriented towards the interior of the building or room to be insulated. Advantageously and according to the invention, said finishing film is similar or identical to the cover film. This is in particular a nonwoven having a breaking strength greater than 150 N, optionally waterproof and permeable to water vapor, made of a material selected from polyesters, viscose rayon , polyolefins and especially polypropylenes, mixtures of several of the abovementioned materials. Its outer face is preferably covered with a reflective metal coating. It is advantageously embossed and / or calendered and / or primed to give the film a better breaking strength. Alternatively, the finishing film incorporates a flexible mechanical reinforcing grid, such as a grid of glass fibers, polyester fibers, polyamide fibers, etc., and has an outer face coated with a reinforcing material mechanical selected from polypropylenes. Note that such a film can also be used as a cover film.

Advantageously and according to the invention, all the layers (film (s) and interlayer (s)) of the material are fixed together by welding or bonding in a limited number of points, called connection points, isolated and distributed on the area of the material. It should be noted that, in the previous insulators, the various layers of the insulation are generally associated by continuous seams, making thermal bridges over long lengths, or glued to each other over their entire surface, so that Significant heat exchange occurs by conduction between two adjacent layers. The various layers of the material according to the invention are, on the contrary, associated punctually to limit the total surface on which they are in conductive contact, as well as the number of thermal bridges possibly generated by these contacts.

Advantageously and according to the invention, the connection points are located outside the insulation openings, and in particular outside the resistive zones of each perforated sheet (so that, at these connection points, the films remain separated by the insulating material constituent of the layers).

The insulation material according to the invention is in the form of (flexible) panels such as strips or substantially square pieces, called slabs. In the following, a panel of material designates a piece of material having, when it is placed on a substantially flat surface, a smaller dimension orthogonal to this surface corresponding to a total thickness of the material, and larger dimensions in a plane parallel to this surface, which delimit two opposite end faces of the panel having a shape any. The peripheral contour of a panel or a layer of the panel (such as a film, a sheet or a series of films and sheets) corresponds to the peripheral contour of a section of said panel or of said layer by a plane parallel to this surface, said front plane of the panel or the layer.

All the layers of a panel, with the exception of the cover film, have substantially identical dimensions in front planes, and form a multicomponent thickener called insulating thickness. Advantageously and according to the invention, the material furthermore has a covering film which protrudes from this insulating thickness along at least a nominal portion of the peripheral contour of said insulating thickness, so as to form at least one overlap strip of an adjacent panel.

The invention extends to a method for laying panels of material according to the invention with regard to a surface to be insulated, characterized in that the panels of material are laid, which are fixed to a support, facing said surface, such that each panel forms, with each panel adjacent thereto, a junction covered with a cover strip and along which the insulating thicknesses of said (adjacent) panels are juxtaposed edge to edge for form a substantially continuous insulating region.

Each covering strip of a panel thus covers a portion (which is, by definition, of the same width as the strip) of the cover film and the insulating thickness of an adjacent panel. Advantageously and according to the invention, each cover strip of each panel is bonded to the cover film of the adjacent panel which it partially overlaps. This operation may be performed by means of an adhesive film, such as a roll tape, which is strapped astride the cover tape and the cover film of the adjacent panel. Alternatively, the inner face of the cover strip, intended to be applied to the cover film of the adjacent panel, is provided with an adhesive coating, protected until the panels are laid, by a removable sheet. Alternatively, a double adhesive tape is used face, which is glued, on the one hand on the inner face of the cover strip, and on the other hand on the cover film of the adjacent panel.

The presence of cover strips formed in the covering film of the panels of material according to the invention makes it possible to maintain satisfactory thermal insulation performance at the junctions of the panels, without it being necessary to provide said junctions with a superposition of the panels (which creates an undesirable oversize). If the roofing film provides a waterproof, drift-free under-roofing screen, the junction will also be impervious to runoff and powder snow, and the material preserved.

Note that the expression "lay the panels facing a surface to be insulated" used above means either that said panels are applied against said surface, in which case the "support" to which the panels are attached refers to on the surface itself, that is to extend the panels away from the surface, substantially parallel thereto, in which case the "support" comprises for example chevrons and / or battens (the surface being that defined by the roof covering for example ...) and / or cleats and / or cleats or other plastic spacers (for a surface such as a ceiling, a wall ...), etc.

Moreover, the expression "nominal portion" above used refers to a portion of the peripheral contour of the insulating thickness of the panel adapted so that, once the panels of material laid according to the invention, all the junctions between panels are normally (except for any exceptions due to the geometry of the surface to be insulated) covered by cover strips.

In a first version of the invention, the panels are in the form of strips (that is to say, strips of great length) and the cover film protrudes from the insulating thickness along an longitudinal lateral right edge of said insulating thickness, said overlap edge, so as to form a longitudinal lateral right overlap strip. The longitudinal lateral edge of the insulating thickness, opposite the overlapping edge, is called simple edge. In in other words, the nominal portion, as defined above, of peripheral contour of a web of material corresponds to a longitudinal lateral edge of the web.

In a second version of the invention, the panels are slab-shaped and the cover film protrudes from the insulating thickness along two lateral edges, said overlapping edges, contiguous or opposite to said thickness. insulation, so as to form two contiguous or opposite lateral straight cover strips. The other two lateral edges of the insulating thickness are said simple edges. In other words, the nominal portion, as defined above, of peripheral contour of a slab of material corresponds to two lateral edges of the slab.

To lay a slab or slab, said second panel, adjacent to a slab or slab, said first panel, already laid and fixed to the support and having a single edge free, we juxtapose a covering edge of the second panel to the free edge simple of the first panel, so that the cover strip of said overlap edge of the second panel covers a portion of cover film and insulating thickness of the first panel to from said simple edge. The second panel is then fixed to the support.

To install a slab or slab, said second panel, adjacent to a slab or slab, says the first panel, already laid and fixed to the support and having an edge of free covering, inserting a single edge of the second panel under the cover strip of the free overlap edge of the first panel so as to juxtapose said single edge of the second panel to the overlap edge of the first panel, so that said cover strip of the first panel covers a portion of cover film and insulating thickness of the second panel from said single edge. The second panel is then fixed to the support.

The invention also relates to an insulation material characterized in combination by all or some of the characteristics mentioned above and below.

• la figure 1 est une vue en perspective d'un lé de matériau selon l'invention, dont une bande longitudinale médiane a été coupée et dont des portions ont été "arrachées" en vue de dévoiler certaines couches (nappe ou film) du matériau,
• la figure 2 est une vue de dessus schématique d'une portion d'une nappe ajourée selon l'invention.

Other objects, features and advantages of the invention will appear on reading the following description which refers to the appended figures representing preferred embodiments of the invention given solely by way of non-limiting examples, and in which:

• the figure 1 is a perspective view of a web of material according to the invention, of which a median longitudinal band has been cut off and whose portions have been "torn off" in order to reveal certain layers (web or film) of the material,
• the figure 2 is a schematic top view of a portion of a perforated sheet according to the invention.

The flexible material according to the invention shown in figure 1 is in the form of a width 1500 mm wide and one or more tens of meters in length. In the following, the term "length" designates a dimension of an element in a longitudinal direction of the web, and the term "width" denotes a dimension of the element in a direction, called transverse direction, orthogonal to this longitudinal direction. and contained in a frontal plane of le. The lé is arranged rolled or folded accordion when transported, and deployed as illustrated in the figure 1 when laid for insulation purposes.

The material comprises a succession of films and perforated sheets, namely: a reflective cover film 1, a perforated sheet 2, a reflecting intermediate film 3, a perforated sheet 4, a reflecting intermediate film 5, a perforated sheet 6, a reflecting intermediate film 7, a perforated sheet 8, a reflecting intermediate film 9, a perforated sheet 10, a reflective finishing film 11. The outer face 12 of the cover film 1 constitutes a front face of the material preferably intended to be oriented towards the outside of the building to be insulated, the outer face 14 of the finishing film 11 constituting the opposite end face of the material, preferably intended to be oriented towards the interior of the building.

Each intermediate film 9, 7 ... is made of polyether (and in particular polyester), and has a thickness of the order of one hundredth or tenth of a millimeter. Its faces 18, 19 are metallized, for example by vacuum deposition of aluminum, and therefore have a high reflectivity. Note that only one face 18 or 19 is metallized to obtain the desired insulating effect, and this, summer and winter (that is to say whatever side is the hot environment) .

The cover film 1 and the finishing film 11 are nonwovens made of polypropylene or polyether, with a mass per unit area of the order of 90 g / m ² . The outer face 12, 14 of said films is embossed over its entire surface (the embossing is only represented in some places) and metallized by deposition of aluminum under vacuum. The inner face 13, 15 of each of these films preferably has no coating (apart from the inner face portion of the cover film 1 corresponding to the cover strip 20, which may be covered with an adhesive coating); its emissivity varies according to the polymer chosen to make the film but remains very low. Such cover and finish films are impervious to runoff and powdery snow, and permeable to water vapor. They both make rainscreen underlays, particularly resistant to tearing and punching.

The width of the cover film 1 is greater than that of the insulating thickness 35 formed by the other layers of the web (webs, intermediate films and finishing film), and preferably measures 1600 mm. The cover film 1 thus forms a cover strip 20 of 100 mm width, long and projecting from a longitudinal lateral edge 21 of said insulating thickness 35.

Each sheet 2, 4, 6, 8, 10 is pierced with insulation lights 17 regularly distributed over three resistive zones 24 (illustrated in FIG. figure 2 ) in the form of continuous longitudinal strips, between which extend longitudinal strips (that is to say without insulation light), also continuous, intended to receive the connection points of the multilayer material. Such resistive zones in the form of continuous strips can easily be made on a web moving along it in its longitudinal direction, by means of simple cutting tools with continuous operation (for example, rotating cylinder provided with cutting blades, and counter-rotating cylinder).

Note that on the figure 2 only a few insulation lights of a resistive (central) zone are represented. It will be readily understood that said zone is entirely pierced with insulation lights, and that this is also the case of the other two resistive zones 24 each delimited by a dashed line.

Each resistive zone 24 extends over a width of 400 mm and along the entire length of the web of material. The distance (in the transverse direction) between each of the edges 21, 22 and the closest resistive zone 24 is of the order of 100 mm. The distance separating two resistive zones in the transverse direction is also of the order of 100 mm.

In the illustrated example, each insulating light is circular and has a diameter of the order of 20 mm. The distance in the transverse direction between two successive insulation lights is of the order of 10 mm. The transverse rows of insulation lights are made staggered: the lights of two successive transverse rows are not facing in the longitudinal direction.

Each perforated sheet has a thickness, at rest (that is to say without any pressure exerted on either side of the sheet), of the order of 8 mm. Note that on the figure 1 , the proportion between the diameter of the insulation lights and the thickness of the sheet is not respected. The plies are preferably polyester textile wadding with a weight per unit area of between 80 and 120 g / m ² .

The various films and sheets are fixed together by ultrasonic welding at a few connection points 25, 26 distributed over the area of the web outside the resistive zones 24. The connection points 25, located in the two lateral solid longitudinal strips 27 , 28 are called lateral connection points; the connection points 26 located in the two central solid longitudinal strips 29, 30 are called central connection points. The lateral connection points are made in the middle of the lateral solid strips 27, 28, that is to say at 50 mm from the edges 21, 22. Similarly, the central connection points 26 are made in the middle of the strips full central 29, 30, that is to say 50 mm from each of the adjacent resistive zones 24. The distance separating two lateral connection points 25, in the longitudinal direction, is of the order of 200 mm. The distance separating two central connection points 26, in the longitudinal direction, is of the order of 400 mm. The two rows of lateral connection points 25 are made such that said lateral points 25 are aligned in the transverse direction. The two rows of central connection points 26 are made such that said central points 26 are staggered (that is to say non-aligned) in the transverse direction, and so that they are also staggered -according to the cross direction - with lateral connection points 25.

At each point of connection, the thickness of the material is of the order of a few millimeters due to the compression of the sheets by the weld. At a distance from the connection points, the thickness of the material varies, at rest (that is to say when the material is laid untended on a flat surface and does not undergo any pressure force), between 40 and 60 mm. These values are greater than the sum of the thicknesses of all the constituent layers (films and sheets) of the material. Indeed, not being glued together, two successive layers touch only in small areas around the connection points. At a distance from said connection points, when the material is at rest, the two successive layers are separated by a more or less thick air layer contributing to the thermal insulation performance of the material. When laying the material, it is advisable not to stretch the material forcibly, in order to fix it in a state as close as possible to its state of rest, and thus to preserve air gaps between the different layers of the material. material. It should be noted that in the stretched state (that is to say when tension forces are exerted on both sides of the web in the transverse and / or longitudinal directions), the material has a thickness which can vary from 20 to 40 mm, and thermal insulation properties that remain quite satisfactory and are better than those of the prior materials.

The outer face 12 of the cover film 1 is preferably oriented towards the outside of the building in all the applications for which the material is likely to experience accidental runoff of rainwater or slush. Thus, the cover strips 20 prevent runoff from infiltrating the junctions between the strips, and protect not only the interior of the building but also the insulating thickness 35 of the material.

In any case, the strips of material according to the invention are normally laid so that the outer face of the cover film is oriented towards the person placing the material, in order to facilitate the bonding operation of each strip. covering to the cover film of the adjacent lé. When the strips are laid on rafters or on battens, the cover film 1 is therefore advantageously oriented towards the outside of the building. Note that for the insulation of a roof or a vertical wall, the strips can be arranged vertically or horizontally.

The first is placed in the usual way and regularly stapled to the support (vices, rafters, trusses, cleats, floor ...). Where appropriate, the longitudinal ends of the web are cut with a conventional cutter. The next lé, said second lé, is set so that its overlap edge 21 comes into contact with the single edge (such as 22) of the first lé, and that its covering strip 20 covers the cover film (such as 1) from the first lé. Alternatively, the second web is placed so that its single edge 22 comes into contact with the overlap edge (such as 21) of the first web, and that the web (such as 20) of the first web overlies its cover film 1. The second piece is then stapled steadily to the backing against which it is applied. The cover strip 20 of the second web (or alternatively of the first web) is then glued to the first web (respectively the second web). For this purpose, the inner face 13 of the cover film 1 is coated with an adhesive coating at the level of the covering strip 20 (and only in this area), protected from a removable sheet. Once the second stapled, the sheet is removed and the cover strip of the second web (or the first) is pressed against the front face of the first web (respectively, the second web). It should be noted that, given the flexibility of the cover film 1, the cover strip 20 of a strip is easily folded to adjust the relative position of the corresponding overlapping edge and the single edge of the adjacent leg, or to peel off the sheet protecting the adhesive coating of said strip.

It goes without saying that the invention may be subject to numerous variants with respect to the embodiments previously described and shown in the figures. In particular, the number of webs and films of the material is not limited to that of the illustrated embodiment. The invention extends in particular to the particular case of a material consisting of a single perforated sheet covered on each side by a reflective film, or covered on one side only by such a film. It should be noted, however, that the superposition of several reflective films makes it possible to reduce the radiation exchanges between two media more effectively.

The invention also extends to the case of a material comprising one or more intermediate layers (bubble films, foam or fibrous material sheets, etc.), since at least one of these intermediate layers is a perforated sheet as defined above.

Furthermore, the invention is not limited to a thin material (less than 10 cm thick). It can be applied to a thicker material, although thin materials are preferred for their small footprint.

On the other hand, the materials mentioned in the description for the production of films and sheets are provided by way of non-limiting examples.

The shape, number and arrangement of the resistive zones and the insulation lights of a perforated web are not limited to those of the embodiment illustrated in FIG. figure 2 . However, according to the invention, the insulation lights are devoid of sharp angle, which excludes polygons. The dimensions of each insulating light are further adapted so that the facing films do not touch through the light, under normal conditions of use and implementation of the material.

In particular, the insulation lights may have an elliptical section, oblong or more complex shape. The perimeter of the light may optionally have one or more rectilinear portions, which can not however be consecutive (these portions are separated by curved portions, so as not to form any sharp angle).

Furthermore, the successive transverse rows of insulation lights can be aligned in the longitudinal direction, in order to simplify the implementation. In addition, transverse strips of solid ply may be provided between successive resistive zones in the longitudinal direction.

Claims (21)

1. A supple thermal-insulation material comprising at least one supple batt (10) and at least one supple film (9), which are superposed, comprising at least one supple batt (10), a so-called perforated batt, that is

   • covered on one side at least by a supple film (9), a so-called reflective film, exhibiting a face that is, at the same time, reflective and hardly emissive, and/or two hardly emissive faces, and/or two reflective faces,

   • and provided with at least one through-hole (17), a so-called insulation hole, containing a volume of gas which normally comes into contact with each portion of film opposite the insulation hole, characterised in that each insulation hole (17) has a frontal cross-section devoid of sharp corners.
2. Material according to Claim 1, characterised in that the perforated batt (10) comprises at least one zone (24), a so-called resistive zone, of greater thermal resistance, in which there are arranged insulation holes (17) defining a total area of opening greater than half of the area of the resistive zone, the totality of said resistive zones extending over more than half of the area of the perforated batt.
3. Material according to one of Claims 1 or 2, characterised in that the perforated batt is made of a non-woven, thermobonded and/or needled and/or adhesion-bonded fibrous material.
4. Material according to one of Claims 1 to 3, characterised in that the perforated batt exhibits insulation holes (17) of circular cross-section.
5. Material according to one of Claims 1 to 4, characterised in that the perforated batt exhibits insulation holes of oval or elliptical cross-section.
6. Material according to one of Claims 1 to 5, characterised in that the dimensions of each insulation hole (17), the thickness of the perforated batt (10) and the suppleness of each film (9, 11) that covers it are adapted so as to avoid any untimely contact, across said hole, between the reflective film (9) and a film (11) or a partition wall opposite the other side of the perforated batt.
7. Material according to one of Claims 1 to 6, characterised in that each insulation hole (17) exhibits a maximal dimension less than ten times the thickness of the perforated batt (10).
8. Material according to one of Claims 1 to 7, characterised in that the perforated batt (10) exhibits a thickness between 1 mm and 12 mm, and in that each insulation hole exhibits a maximal dimension between 10 mm and 30 mm.
9. Material according to one of Claims 2 to 8, characterised in that the insulation holes of a resistive zone are aligned in a longitudinal direction and in a transverse direction of the material.
10. Material according to one of Claims 2 to 8, characterised in that the insulation holes (17) of a resistive zone (24) are arranged in staggered manner.
11. Material according to one of Claims 2 to 10, characterised in that the resistive zone or zones form one or more longitudinal or transverse bands in the perforated batt.
12. Material according to one of Claims 1 to 11, characterised in that it exhibits a total thickness of less than 10 cm.
13. Material according to one of Claims 1 to 12, characterised in that each perforated batt (2, 4, 6, 8, 10) is covered on each side by a reflective supple film (1, 3, 5, 7, 9, 11).
14. Material according to one of Claims 1 to 13, characterised in that each perforated batt (2, 4, 6, 8, 10) is a wadding or a felt or a flannelette consisting of a non-woven fibrous material that is produced from a material chosen from among the synthetic materials made of polyester, polyamide, chlorofibres, polyolefin, the artificial materials such as viscose rayon, the natural materials of vegetable origin, such as cotton, hemp, flax, the natural materials of animal origin, such as sheep's wool, mixtures of several of the aforementioned materials.
15. Material according to one of Claims 1 to 14, characterised in that it comprises a film (1), a so-called covering film, exhibiting an external face (12) forming a front face of the material, and in that said covering film (1) is impervious to water and permeable to water vapour, and exhibits a rupture strength greater than 150 N.
16. Material according to Claim 15, characterised in that the covering film is a nonwoven produced from a material chosen from among the polypropylenes, the polyesters, viscose rayon, mixtures of several of the aforementioned materials, and in that its external face (12) is embossed and/or calendered and/or finished and is covered by a reflective metallic facing.
17. Material according to one of Claims 1 to 16, characterised in that it is formed from layers (1, 3, 5, 7, 9, 11; 2, 4, 6, 8, 10) which are fixed to one another by soldering or by adhesion bonding at a restricted number of points (25, 26), so-called coupling-points, which are isolated and distributed over the area of the material.
18. Material according to Claim 17, characterised in that the coupling-points (25, 26) are situated outside the resistive zones (24) of each perforated batt.
19. Material according to one of Claims 1 to 18, taking the form of panels, characterised in that it is formed from layers (1, 3, 5, 7, 9, 11; 2, 4, 6, 8, 10) which, with the exception of a film (1), a so-called covering film, exhibit approximately identical dimensions in frontal planes and form a multi-component insulating thickness (35) and in that the covering film (1) projects from the insulating thickness (35) along at least one nominal portion of the peripheral contour of said insulating thickness in such a manner as to form at least one overlapping band (20) of an adjacent panel.
20. Material in strip-form according to Claim 19, characterised in that the covering film (1) projects from the insulating thickness (35) along a longitudinal lateral straight edge (21) of said insulating thickness, a so-called overlapping edge, in such a manner as to form a longitudinal lateral straight overlapping band (20).
21. Material in slab-form according to Claim 20, characterised in that the covering film projects from the insulating thickness along two lateral straight edges, so-called overlapping edges, which are contiguous with or opposite said insulating thickness, in such a way as to form two contiguous or opposite lateral straight overlapping bands.

Images